Integrated circuits (IC) are the cornerstone of the information age and the foundation of today's information technology industries. The integrated circuit, a.k.a. “microchip,” is a set of interconnected electronic components, such as transistors, capacitors, and resistors, which are etched or imprinted onto a tiny wafer of semiconducting material, such as silicon or germanium. Integrated circuits take on various forms including, as some non-limiting examples, microprocessors, amplifiers, Flash memories, application specific integrated circuits (ASICs), static random access memories (SRAMs), digital signal processors (DSPs), dynamic random access memories (DRAMs), erasable programmable read only memories (EPROMs), and programmable logic. Integrated circuits are used in innumerable products, including personal computers, laptop and tablet computers, smartphones, flat-screen televisions, medical instruments, telecommunication equipment, networking equipment, airplanes, watercraft and automobiles.
Advances in integrated circuit technology and microchip manufacturing have led to a steady decrease in chip size and an increase in circuit density and circuit performance. The scale of semiconductor integration has advanced to the point where a single semiconductor chip can hold tens of millions to over a billion devices in a space smaller than a U.S. penny. Moreover, the width of each conducting line in a modern microchip can be made as small as a fraction of a nanometer. The operating speed and overall performance of a semiconductor chip (e.g., clock speed and signal net switching speeds) has concomitantly increased with the level of integration. To keep pace with increases in on-chip circuit switching frequency and circuit density, semiconductor packages currently offer higher pin counts, greater power dissipation, more protection, and higher speeds than packages of just a few years ago.
Conventional microchips are generally rigid structures that are not designed to be bent or stretched during normal operating conditions. Likewise, most microchips and other integrated circuit modules are typically mounted on a printed circuit board (PCB) that is similarly rigid. Processes using rigid IC's and rigid PCB's are generally incompatible for applications requiring stretchable or bendable electronics. Consequently, many schemes have been proposed for embedding microchips on or in a flexible polymeric substrate to create a flexible electronic circuit system. To ensure constant and reliable electrical connections between individual IC modules, many flexible circuits employ stretchable and bendable interconnects that remain intact while the system stretches and bends. This, in turn, enables many useful device configurations not otherwise possible with rigid silicon-based electronic devices.
High quality medical sensing and analysis has become important in the diagnoses and treatment of a variety of medical conditions, including conditions related to the digestive system (e.g., liver and stomach), the cardiovascular system (e.g., heart and arteries), the nervous system (e.g., brain and spinal cord), and the like. Current medical sensing devices suffer from various disadvantages due to a lack of sophistication in sensing, analysis and therapeutic technology. One disadvantage is that many contemporary sensing and analysis devices are unable to achieve direct and conformal contact with the body of the patient. The inability to achieve direct or conformal contact is typically attributable to the rigid nature of the devices and accompanying circuitry. Such rigidity prevents these devices from coming into conforming and direct contact with human tissue, which may change shape, size, and/or orientation, and may be soft, pliable, curved, and/or irregularly shaped. This, in turn, can compromise the accuracy of measurements and the effectiveness of treatment. Thus, devices, systems and methods that employ flexible and/or stretchable systems for medical sensing, analysis and diagnostics would be desirable.